


If You Love Him (Set Him Free)

by ZairaA



Category: Merlin (TV)
Genre: Alternate Universe - High School, Alternate Universe - Modern Setting, Coming of Age, F/M, Falling In Love, M/M, Manipulation, Multi, Sexual Coercion, Shameless Smut, Sibling Incest, Threesome
Language: English
Status: Completed
Published: 2014-09-21
Updated: 2014-09-21
Packaged: 2018-02-18 05:56:48
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,384
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2337674
Author URL: https://archiveofourown.org/users/ZairaA/pseuds/ZairaA
Summary: <blockquote class="userstuff">
              <p>Morgana and Arthur are the polar opposites and yet they share a bond that goes beyond the love of siblings. Arthur is the only constant in Morgana's life and she's not prepared to give him up when Arthur starts to notice there's someting about one Merlin Emrys. Thinking she can use Merlin to her own ends, Morgana makes her move.</p>
            </blockquote>





	If You Love Him (Set Him Free)

**Author's Note:**

  * For [alby_mangroves](https://archiveofourown.org/users/alby_mangroves/gifts).



> Happy Birthday, Alby! I hope you like my shitty and hastily baked Porn Cake a little. Thank you for being a wonderful person ~~and making me want to write incestuous threesomes~~! Feel hugged and inappropriately groped!  <333

Merlin was sure he must have misheard. There simply was no way Morgana Pendragon had just asked him out on a date, and Merlin hastily closed his mouth when he realised he was giving a rather unattractive impression of a fish. It wasn't that Merlin was chopped liver; it was just that he most certainly wasn't in the league of someone like Morgana, who not only was a senior, but also easily the most beautiful and the most intimidating girl at school.   
  
Morgana raised an elegant eyebrow and looked him up and down with an air of amusement. ''Come around tomorrow night at eight,'' she said because, apparently, Merlin's agreement was beyond question. Not that Merlin would have said no. That would be absurd; no one said no to Morgana.  
  
So Merlin nodded quickly, any words he might have been able to form still stuck in his throat, and then his stomach dropped to somewhere around his ankles because a little further down the hall stood Arthur, Morgana's brother, glowering at him as if he was taking offence in the sole fact that Merlin existed – something Merlin was sure Arthur had not even taken notice of up to this point.  
  
If Morgana was the glamorous queen of the night, all mysterious grace and wicked smiles, Arthur was like her first knight: blond, haughty and perfect in everything he did. Unlike with Morgana there were no rumours about drugs and scandalous affairs, instead Arthur had an air of cold arrogance, distant apart from his obvious protectiveness in regard to his sister. Now his blue eyes were piercing Merlin to the core, his expression unreadable.   
  
Morgana turned her head a little, as if she was about to look over her shoulder, but her gaze remained on Merlin, her smile acquiring a hint of smugness now. Then she leaned forward and brushed her lips against Merlin's burning cheek.   
  
''I'm looking forward to it,'' she murmured, her voice dark and seductive. ''I'm sure it will be a very interesting night.''  
  
She walked away then, hips swaying and without any further explanation, and for a moment Merlin wasn't at all sure he had not dreamed up the whole encounter. Only that Arthur was still glaring at him as if he was trying to incinerate Merlin with his mind alone.   
  
When Merlin rang the bell at Morgana's place the next day he wasn't certain what he was more nervous about, the prospect of spending time with Morgana or the prospect of her brother probably murdering him soon after.   
  
  
  
Seducing Merlin was incredibly easy. The boy was still a virgin and, although Morgana usually preferred her men more experienced, she couldn't deny that there was something about his eager innocence. Morgana was used to having to barter and manipulate to get what she wanted and, while there was a certain thrill in that of its own right, Merlin's willingness to please her was refreshing. Even if it made this game almost ridiculously easy.  
  
She had expected her brother much earlier, as soon as she was back from her date with Merlin to be honest, and so she wasn't surprised when she caught a glimpse of him in the mirror of her dresser as she was getting ready for bed. She watched him, silently standing in the doorway, while she kept brushing her hair. She was only in her bra and panties, but it wasn't as if he had not seen much more of her before.  
  
''What the hell do you think you are doing, Morgana?''  
  
His voice was a low hiss, and Morgana turned around slowly, letting a derisive smile crawl up around the corners of her mouth.  
  
''Whatever are you talking about?''  
  
''You know what I'm talking about. What are you doing with him?''  
  
Oh, this was perfect. Morgana's smile broadened.  
  
''Do you want to know? I'll tell you.''  
  
Arthur's nostrils flared, and Morgana was sure, if she would take a closer look, she would find his cock hard in his trousers. But right now, she didn't let him escape her gaze.  
  
''He has the most sinful mouth, don't you think, dear brother? Those lush lips. Mhmm... do you want to know what they felt like?''  
  
Arthur swallowed hard. But then he nodded, so very very reluctantly. Arthur had always been her favourite to play with.  
  
''Come here then.'' Morgana held out her hand. ''I'll show you exactly what we did.''  
  
She pulled down the strap of her bra in a lascivious gesture, letting her left breast fall free and circling the hardening nipple with her thumb.   
  
''That's where his lips were, Arthur, just a little while ago. You might still be able to taste him.''  
  
Arthur's blue eyes were caught on her breast as if he was hypnotised, slowly stepping forward until he was right in front of her, sinking to his knees to bring him down to her level. Morgana shivered, leaning back on the stool and arching her back a little, offering what they both knew he wanted.  
  
Arthur's lips were cool on her heated skin at first, almost shocking, but his mouth was hot and wet and his tongue sleek and delicious. Morgana moaned, balling her hands into fists to keep from reaching for him, keep from pulling him harder against her. She knew that would only result in him fighting back.   
  
Her breath became sharper as her brother sucked on her nipple and she slid one slender hand between her thighs and inside the lace of her panties, touching her already wet folds.   
  
''Do you want to know where else Merlin licked me?'' she whispered, smiling triumphantly when Arthur shuddered against her. 

  
  
Arthur knew he was weak and he hated himself for it. He loved his sister, loved her dearly, and he knew what they did was wrong, never mind that Morgana told him not to get hung up on some stupid rules society had made up. Morgana had always been self-destructive and Arthur's job had always been to protect her but somehow she had turned that around on him and made him into one more thing she used to rip her life apart at the seams.  
  
It had been so innocent at first. Cuddles and hugs, taking comfort in the warmth of each other in a house where so little comfort was to be had. It had taken him a while to understand that, at fifteen, people didn't usually cuddle with their older sister any longer. Especially not in said sister's bed, and not half naked. But it had probably been too late by then because, at fifteen, Arthur's hormones were also rampant, his cock completely out of control, and the first time he had an erection during one of their snuggling sessions, Morgana had just taken hold of it inside his pants, as if it was the most natural thing in the world.  
  
''Don't be ashamed,'' she had said with a soft chuckle. ''It's normal. Want me to show you how good it can feel?''   
  
He could have said no then, should have said no, he knew that now. But her hand on his cock had been the most brilliant feeling he had ever experienced and all he could do was buck into her touch helplessly, spurting all over her fingers a moment later.  
  
It had been a line crossed, a point with no return, and it had felt so bloody good that it had not taken much to convince Arthur that it was okay to do it again. To go further.   
  
It was never about romance, Arthur knew that Morgana slept with all kinds of men, but Arthur was the one constant, the one thing that kept her grounded even if it was in a horrifyingly twisted way. Sometimes they would go a week or two without so much as a too intimate kiss, and then Morgana would slip into his bed in the middle of the night, drape herself against his back and stroke him awake until he was already too far gone to deny her. Or maybe that had just been a convenient excuse.  
  
And then Merlin Emrys happened.   
  
  
  
Merlin wasn't entirely sure how he had come to be here. In Morgana Pendragon's room. In Morgana Pendragon's bed. Kissing Morgana's naked breasts for a _second_ time – because it was public knowledge that Morgana didn't do second dates. Not that Merlin would call what they had done so far dating, exactly. It was more like frantic romps, or well, Merlin was a little frantic while Morgana seemed all cool and collected, telling him exactly what she wanted which was strangely hot and also a bit of a relief because it kept Merlin from embarrassing himself too much, fumbling around without a clue.  
  
He still had no idea what had made Morgana pick him of all people, maybe she just had been in the mood for Irish virgin boy, but what had completely shocked him was when she had come up to him at school two days after their first _encounter_ , trailing her fingers along the nape of his neck and leaning in close to whisper in his ear.  
  
''Come over tonight if you want to learn how to fuck.''  
  
Having an instant erection was not a hard feat for a teenage boy like Merlin, but for a moment he had been almost sure he would jizz in his pants.  
  
''O-Okay,'' he had croaked, entirely too high-pitched, which made Morgana chuckle.  
  
''Eight o'clock. I'll have a surprise for you.''  
  
Merlin had mostly forgotten about that promised surprise - hardly difficult when pretty much all Morgana did was somewhat startling and also shockingly arousing. Being in Morgana's bed was at the same time more comfortable and more awkward than groping around on the back seat of a car in the dark, and Merlin swallowed hard looking down at her, stretched out on the sheets in all her naked glory and still looking like a queen.  
  
''Come on, Merlin,'' Morgana drawled. ''None of that. You don't need to be shy. Lose those pants, so that I can see all of you.''  
  
Fumbling to pull his underwear down and off his legs while crouching in front of her, put another blush on Merlin's cheeks and his erection wilted a little from his nerves.   
  
''Look at you,'' Morgana murmured through a devilish smile. ''I'm sure he will like you.''   
  
Merlin had only a second or two to wonder what she was talking about before Morgana turned her eyes away from him and towards the door. ''Don't you, Arthur?''  
  
Merlin froze. A glance over his shoulder confirmed the presence of Morgana's brother, standing in the shadows just beyond the reach of the light from the bedside lamp, his face unreadable. Merlin's whole body turned stiff and so, embarrassingly, did his cock.  
  
Pushing herself up to a sitting position, Morgana let her hands glide up over Merlin's shoulders and then down his back, all the while keeping her eyes locked on her brother.   
  
''I promised him to show him how to fuck. But there are some things I'm sure you'd be better qualified to teach him, don't you?''   
  
Merlin could hardly breathe when he felt her cool fingers travel down his spine towards the crack of his arse.   
  
''I mean, I could peg him, of course. And maybe I'll do that later. You always enjoyed that didn't you? But I'm sure Merlin would like to find out what a real cock feels like inside of his arse.'' Her other hand cupped Merlin's burning face and turned it upwards to meet his eyes. ''Am I right, darling? Do you want Arthur to fuck you while I make you eat me out?''  
  
Merlin stared into her merciless eyes for a long moment before he breathed a soft, almost inaudible, ''Yes.''  
  
  
  
Arthur felt frozen in place, just outside Morgana's door, although every rational thought he was still able to gather told him to turn around and walk away. That he had to resist and not give in to one more of Morgana's twisted games. Unfortunately there weren't many rational thoughts left at the sight of Morgana's fingers sliding into the cleft parting Merlin Emrys' pale and perfect arse. Instead most of his brain capacity was occupied with images of sliding up on the bed behind the other boy, bending down to bury his face between those cheeks and taking in the smell and taste of all that was Merlin.  
  
God, Arthur wanted. Had wanted ever since Merlin had returned to school after the summer holidays, obviously having gone through a late growth spurt and finally able to pull off the sharp features of his face. What had been a weird assembly of hard angles and plush curves was now a graceful symphony that Arthur could have watched all day long. The only thing he might want more was to make them distort in pleasure and ecstasy. And of course Morgana knew that.  
  
''You should take off your clothes,'' Morgana's voice filtered into his mind, and Arthur became aware that his knees were bumping against the bed frame. He hadn't even realised that he had stepped inside the room, and here he was, so close that he just had to reach out and be able to touch the round globes of Merlin's arse.   
  
The breath he released came out as a moan and, when he met Morgana's eyes, her gaze was knowing but without any of her usual smugness. And maybe that was what gave him the last push. _I'm doing this for you,_ her look seemed to say. _This is my present for you._  
  
He pulled his t-shirt over his head in a daze and unbuckled his trousers mechanically. Making this one of Morgana's requests was easier than facing his own jumble of desire and emotion, but only until he tentatively reached out and curled his broad palm over Merlin's hip, making the other boy shudder.

Suddenly all he could think about was Merlin and how much he wanted him, Morgana becoming almost an after thought. But of course Morgana wouldn't let him forget so easily.

''That's it. Touch him,'' she whispered. ''Feel how smooth his skin is. Lovely isn't it?''  
  
''Yeah,'' Arthur breathed, completely enthralled, running his hands all over Merlin's back and buttocks.   
  
Morgana chuckled. ''Spread his cheeks and take a look. I'm sure he's even prettier inside, all pink and innocent, where no one else has touched him before.''  
  
The thought of being the first to ever have Merlin like this made Arthur groan and he couldn't hold back. He let his thumbs part Merlin, like he was splitting a fruit, revealing the tender flesh inside, the delicious ripe smell, imagining how sweet he would taste. He bent forward and took a tentative lick. From Merlin's pink taint, over the wrinkled furl of his hole and all the way up to his tailbone.   
  
There was a dual moan coming both from Merlin and Morgana, and Arthur glanced up to see his sister lean back against the pillows at the headboard, dragging Merlin down between her spread legs by the curls at the back of his head. The new position pushed Merlin's arse even further up, so Arthur wasn't about to complain but went back to his curious and intoxicating exploration.   
  
He found out that Merlin liked it when he scraped his teeth along the rim of his crack, that lapping at his hole made him moan and swivel his hips but stabbing his tongue against the tight ring of his pucker made him shudder and tense and buck his arse backwards.   
  
Arthur's own cock was hanging full between his legs, throbbing and straining against thin air, desperate to be touched. But Arthur refrained. He was quite good by now at denying himself, pushing his arousal higher and higher just from the anticipation of what was to come. And he wanted to be buried inside Merlin's tight arse when he came, watching himself move in and out that pink, stretched rim, hearing Merlin's muffled moans against Morgana's pussy.   
  
When Merlin was a whimpering, writhing mess, his cock leaking all over Morgana's sheets and Morgana had bucked herself against Merlin's face through her first orgasm, Arthur finally couldn't wait any longer. He procured the bottle of lube and a condom from Morgana's bed stand and then positioned Merlin a little further up the bed, his mouth against Morgana's breast now.   
  
''God, you're almost ready for me already, aren't you Merlin?'' Arthur moaned, pushing two of his lubed fingers inside Merlin's hot channel. ''So hot and wet and perfect.''

Merlin whimpered.  
  
''Sshhh...'' Morgana stroked Merlin's hair, holding him against her chest as if he was a small child. ''Don't fret, darling. Arthur will take care of you. He has a lovely, fat cock. It will feel so good going up your tight hole, believe me.''  
  
She guided Merlin to one of her dark nipples and Merlin immediately began sucking on it. He was pushing his arse back against Arthur's fingers more and more desperately and Arthur watched entranced until Morgana's voice once more pulled him back.  
  
''Fuck him, Arthur. Come on, take his tight little arse. I want to see your cock splitting him open. He wants it. Don't you, Merlin?''  
  
Merlin's answer was another whimper and a frantic nod. It was more than Arthur could take and so he quickly fumbled with the condom, rolling it down his shaft before lining up against Merlin's winking hole. He held Merlin steady with one hand against the boy's bony hip, but his gaze met Morgana's when he thrust forward into the tight heat of Merlin with a broken sigh.   
  
For a moment he thought that his sister must have seen something there that Arthur wasn't quite aware of because her eyes widened almost in shock, but that soon was forgotten as his own eyes fluttered closed in ecstasy. Everything seemed to fall away as Arthur wrapped himself around Merlin's slender form below him, rocking into him with long, smooth strokes, revelling in the boys desperate moans and thinking that this was what he had been waiting for. This was perfection.

 

  
Watching Arthur fuck Merlin was both mesmerizing and sobering. Her brother's broad frame dwarfed the slighter boy, taking possession of him with all that protective strength that had formerly been reserved for her. In a spike of anger and arousal she pushed Merlin's head back between her legs, making him lick her and suck her with an almost spiteful determination, as if this could take away Arthur's enraptured expression, as if she could somehow drive herself like a wedge between them.   
  
Merlin obeyed her, but his enthusiasm was all for Arthur now and when she came for the second time with his face pressed forcefully against her cunt while watching Arthur come apart, holding on to Merlin like he was a lifeline, her orgasm left her feeling hollow like never before.  
  
Both boys slumped down on the bed next to her exhausted, Arthur coming to rest on Merlin's other side and curling around him with a satisfied sigh. It was strangely symbolic to have Merlin between them. Him the one who got wrapped in Arthur's strong arms now.   
  
Morgana waited until their breaths evened out before she silently slipped out of bed. They looked so adorable together, Arthur's blond tousled head resting on Merlin's shoulder and Merlin holding Arthur's forearm pressed against his stomach, that she felt almost worse for begrudging them this. Begrudging her brother this. Maybe the time had truly come that he had outgrown her.    
  
She was about to turn away and leave, let them have their intimate togetherness without her, when Arthur's voice came quiet but firm from the dark.  
  
''Morgana.''  
  
She turned back hesitantly, wondering when she had become the uncertain one, only to find Arthur holding out his hand towards her in invitation.  
  
''Come back to bed,'' was all he said, scooting over a little to make more room for her on his other side.   
  
She knew it couldn't last. The damage was done and Arthur had begun to slip from her grasp irrevocably. But he was still her brother and she loved him and always would.  
  
Taking his hand she slipped into the bed next to him, snuggling against his broad chest and closed her eyes.  
  



End file.
